It pays for these bird parents to swap feeding duty

"Our research shows that for long-tailed tits at least, coordinating and alternating parental responsibilities like feeding can mean the difference between life and death for chicks," says Kat Bebbington. (Credit: "long-tailed tits" via Shutterstock)

Songbirds called long-tailed tits are more successful at raising young when they alternate their feeding trips, report researchers.

A new study shows parents who take turns feeding their chicks in the nest give the young more food and better protect them from being eaten by predators, compared to those who give them food at random intervals.

This is the first time the strategy, which is similar to humans sharing late night feedings, has been shown to benefit the family group.

“Parents with a young baby often take it in turns to do the grueling night time feeds so that neither of them gets too exhausted,” says lead author Kat Bebbington. “This is a situation we are all familiar with as humans, but there’s almost no evidence for animals doing this in nature.

“Our research shows that for long-tailed tits at least, coordinating and alternating parental responsibilities like feeding can mean the difference between life and death for chicks.”

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The research, which appears in the journal Behavioral Ecology, suggests that parents who take turns visiting the nest do so by making sure they both arrive at the nest at the same time.

This strategy allows them to keep an eye on whose turn it is to feed, but also means that, over the course of the day, parents spend less time near the nest than they would do if each visited the nest alone.

Scientists think this is the reason why chicks are less likely to be eaten if their parents take turns to feed them—visually-based predators like foxes and crows are less likely to be attracted to the nest if the parents are not flying around it as often.

“Most animals provide care for their young, but birds and people are unusual because care is often provided by both parents. This situation generates conflict between the parents because each of them would like their partner to take a greater share of parenting effort. How parents negotiate to resolve this conflict has rarely been investigated, but ‘tit-for-tat’ alternation of visits provides one potential solution to the problem,” says Kat.

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“Our study is the first to show that parents who coordinate care better are more successful in raising young. This clear benefit is a substantial step forward in our understanding of how parenting evolves.

“This “tit-for-tat” style bargaining might also work in other areas of life—at work we all negotiate our tasks with others to make sure the workload is shared, and in nature animals can do the same when feeding offspring, fighting predators, or sharing food.”

Source: University of Sheffield